Perez fastest for second morning running

Sergio Perez remained at the top of the timesheets as the final pre-season test entered its second day on Friday morning in Bahrain.

The Force India driver was 0.280s shy of his best time on the opening day, but it was still enough to end the morning session 0.064s clear of Fernando Alonso's Ferrari in second place. It's unlikely any of the teams have shown their true pace so far this week as they are still lapping roughly two seconds off the best time set by Nico Rosberg and Mercedes last week. Add to that differing fuel loads, tyre compounds and priorities among the teams and the situation is clouded further.

The morning saw two red flags for Mercedes-powered cars when Lewis Hamilton stopped on track after an hour in his factory Mercedes and then Jenson Button pulled over with a problem on his McLaren one and a half hours later. Mercedes wasted no time diagnosing and fixing the issue on Hamilton's car and by the lunch break he had completed a total of 61 laps - the most of any driver in the morning session.

Button's problem appeared to be a little more troublesome as his car spent the rest of the morning in the garage to allow his team to investigate. McLaren is holding its final test upgrades until the weekend in the hope of debugging as many issues as possible on Friday and will be keen to get the car back on track as soon as possible after lunch.

Red Bull had another slow start to the day with only four laps completed in the first three hours. Several crates of new parts arrived in the paddock overnight, suggesting the team is throwing everything at the car to try to rectify its overheating issues. By lunch Daniel Ricciardo had completed 15 laps but was still some way off the pace and will be keen for more mileage in his final session in the car before Melbourne this afternoon.

Lotus also had a slow start to the day before putting in a longer run ahead of lunch. The times suggest both Lotus and Red Bull were still working on getting their cars running reliably, which will be a concern for engine-supplier Renault which is hoping to complete race simulations over the next two days with its teams. The other Renault-powered teams, Toro Rosso and Caterham, had more laps, but were still between four and seven seconds off the pace.

It was a better morning for Marussia as Jules Bianchi managed 33 laps in the MR03 and set the fourth fastest time, 2.628s off Perez. He was fast through the middle sector speed trap, which suggests the Ferrari engine was working well, but could just be a sign that the car is lacking downforce. After a troubled few days in testing so far, it will be interesting to see if Marussia can start to run reliably and relatively quickly, as a race finish in the opening races could be rewarded with points if other cars fail to finish.